1. Field of the Invention
This invention relates to a metallic material capable of preventing or curbing attachment thereto of marine organisms.
2. Description of the Prior Art
When ships are polluted by the attachment of marine organisms to the shells, particularly the underwater surfaces, of their hulls, their speeds are lowered and their fuel economies are degraded. By this reason, there has been an established practice of coating the surfaces of their hulls with pollution-proofing paints containing such pollution-proofing agents as copper suboxide and organic compounds of tin or using metallic materials such as copper, cupro-nickel (Cu-Ni alloy), zinc and silver which exhibit excellent resistance to the pollution.
These pollution-proofing paints and pollution-free metallic materials nevertheless have demerits of their own as shown below.